In various manufacturing and technical assembly applications, such as woodworking and metalworking, it is important to accurately set and measure angles to ensure the components of a workpiece, jig or machine are precisely oriented relative to each other. Currently, the setting and measurement of angles relies primarily upon various protractor devices or sine bars. But protractor devices, such as the ruler and protractor head of a combination square, lend themselves to less than precise angular measurements. Such inaccuracy is caused both by the design of the devices and by operator error. Positioning the protractor to reflect the correct angle can be difficult, especially to the unskilled operator. Even if properly positioned, many protractors are able to measure, at best, one-degree increments. Therefore, an angle setting or measurement read from a protractor is frequently accurate only to the nearest degree. Smaller, fractional increments are not available. Additionally, differentiating between the one-degree increments when the protractor is in use can be difficult, oftentimes leading to inaccurate readings by the user.
While sine bars are more precise, they are more expensive, complex to use, and require a strong understanding of trigonometry, and thus their enhanced precision can be compromised by user error as well. Therefore, a need exists to provide a device that both enhances the precision of angle measurements and settings and simplifies the process. Another usable device is described in U.S. Pat. No. 6,148,531, which converts linear measurements into angular settings. While versatile, this prior device can be difficult to use with desired accuracy in certain situations and requires manipulation and manual alignment of at least two different assemblies during use rather than one unified assembly.
This invention provides an angle gauge that, when used in conjunction with a caliper or other linear measuring device, improves both the precision and ease with which angles can be measured and set by allowing the user to accurately measure and set angles in fractions of degrees. Using the gauge, an angle formed by the gauge may be determined or set by reference to the linear distance measured by the caliper. Calculations or tables can be used to convert the linear measurements into the angle setting or measurement with great accuracy, or the capacity to calculate the angle corresponding to the linear measurement can be built (i.e. programmed) directly into the device.
The gauge is first mounted on the arms of a caliper. To set a particular angle, the user locates on the table the distance between the caliper arms that corresponds to the desired angle and sets and locks the caliper arms at that distance, which automatically positions the arms or wings of the gauge at the desired angle. Similarly, to measure an angle between two reference structures, the user positions the gauge wings in contact with the reference structures, notes the distance on the caliper when the gauge is so positioned, and consults the table to locate the angle measurement corresponding to that distance. Auxiliary arms may be added to the gauge to provide additional ranges of angles for measurement and setting.
In the angle gauge of this invention, two reference wings are pivotably joined to move through 90 degrees of movement relative to each other while each wing is coupled to a caliper arm and the caliper arms move between a fully closed and an open position. An auxiliary right angle attachment arm may be attached to each wing, in effect adding or subtracting 90 degrees from the angular relationship between the wings.
It is an object of the present invention to improve the precision and ease with which angles can be measured and set.
It is another object of the present invention to provide a system that converts a linear distance into angular measurements.